In its path through the environment, water dissolves many substances and suspends many others. The type and concentration of these impurities vary greatly depending upon the source of the water, the environment through which it passes and the regional climate. These particles may be made up of clay, algae, silt, organic and inorganic colloids, and microbes. The initial stages of water treatment may be designed to remove as many of the suspended particles as possible, thereby preparing the water to be filtered. If such material is not removed before filtration, it may reduce the effectiveness of, and eventually clog, the filters. Disruption of the filters may render the water treatment process ineffective.
Water treatment generally has several stages. The first stage may be coagulation. During coagulation, a chemical, such as polyaluminum chloride, may be rapidly mixed into the water. This chemical may neutralize the (typically negative) electrical charges that are present on the small, suspended particles.
The next stage may be flocculation. During flocculation, the water is gently mixed to increase the number of collisions between the small, suspended particles. The colliding particles, which may have been neutralized due to effective coagulation, may stick together to form larger particles called flocs. The goal of flocculation is to create flocs that will rapidly settle out of the water, thereby reducing the number of impurities present in the remaining water. The leftover water may then be filtered to remove any remaining particles.
In addition to the design of the settling basin, physical characteristics of the flocs, including their size, density and shape, are significant in determining the flocs' settling rate. Thus, it would be advantageous to the water treatment process if these parameters were monitored during flocculation to enable optimization of the process's operational parameters including concentration of coagulant and coagulant-aid chemicals and the intensity of mixing of water.
The aforementioned physical characteristics may be challenging to monitor using standard methods including systematic sampling and flow-through monitoring. In this context, systematic sampling may refer to the collection of a volume of water at regular intervals for analysis. This type of systematic sampling necessitates additional resources (personnel and time) and may disturb the particles during treatment. Flow-through monitoring may refer to a system in which a stream of water is diverted to a cuvette for analysis. This method is problematic because flocs may break due to the flow patterns in the sampling device. In addition, the size of the tubing and cuvette limit the size of flocs that can be analyzed.
There is no known automatic process or system that can monitor, and evaluate the size, density, and type of floc and/or other material in the water in situ during treatment.
Thus there is a need for an apparatus and system that can overcome the above listed and other challenges and disadvantages.